Navien Error Code E615: PCB Communication Failure
Warning: Your Navien boiler has a communication issue, causing it to shut down. It's safe to troubleshoot, but call a professional if needed.
How to Fix Navien Code E615
- Step 1: Check if the boiler has power. Look for the 'ON/OFF' switch and ensure it's in the 'ON' position.
- Step 2: Try a power reset. Turn off the boiler at the switch, wait 30 seconds, then turn it back on.
- Step 3: If the error persists, call a professional HVAC technician. Do not attempt to open the boiler or tamper with internal components.
How to Reset Navien Code E615
- Turn off the unit using the power button on the front panel.
- Turn off the gas supply valve.
- Turn off the circuit breaker supplying power to the unit. Wait 30 seconds.
- Restore power at the breaker, then open the gas valve.
- Turn the unit back on. If the error returns, the underlying issue needs repair.
Resetting clears the code from the display but does not fix the underlying fault. If the code returns after reset, proceed to the diagnostic steps above.
What Does Navien Error Code E615 Mean?
The E615 error on your Navien boiler indicates a PCB (Printed Circuit Board) communication failure. This means that the control board can't communicate properly with other components, causing your boiler to shut down. This issue is typically not caused by a faulty PCB itself, but rather a problem with the communication lines or other connected components.
Common Causes
- Wiring issues or damaged communication lines
- Faulty sensors or other connected components
- Software glitch causing temporary communication failure
Diagnostic Steps
| If... | Check | Expected |
|---|---|---|
| Boiler doesn't power on | Check if the 'ON/OFF' switch is in the 'ON' position and if there's power at the switch | Switch in 'ON' position and power present |
| Boiler powers on but displays error | Inspect the wiring harness and communication lines for any damage, corrosion, or loose connections | No damage or issues found |
Applicable Navien Models
Source Documentation
Referenced in 6 official Navien technical manuals.
| Manual | Page | Reason | Action |
|---|---|---|---|
| NFB-H Installation & Operation Manual | 116 | Abnormal Memory | Check PCB connections. |
| Navien NCB-H Installation & Operation Manual | 130 | Abnormal Memory | Contact technical support at 1-800-519-8794. |
| Navien NFB-H Installation & Operation Manual | 116 | Abnormal Memory | Check PCB connections. |
| Navien NFC-H Installation & Operation Manual | 128 | Abnormal operation: input and memory | Manual RESET Auto RESET Alarm |
| Navien NHB-H Installation & Operation Manual | 119 | Abnormal Memory | Check PCB connections. |
| Navien NPF Installation & Operation Manual | 128 | Abnormal overheat controller feedback | — |
Replacement Parts
| Part | OEM Number | Est. Cost | Where to Buy |
|---|---|---|---|
| Communication Line Harness | 900-1100-0000 | — | Find Part |
| PCB (Printed Circuit Board) | — | — | — |
Related Codes on Same Models
Other codes that affect the same Navien model families as E615.
| Code | Description | Severity |
|---|---|---|
| E001 | Ignition Failure | Warning |
| E003 | Abnormal Ignition | Warning |
| E004 | False Flame Detection | Warning |
| E031 | Inlet Thermistor Open/Short | Warning |
| E046 | Outlet Thermistor Open/Short | Warning |
| E110 | Exhaust Blocked | Warning |
| E205 | Water Flow Sensor Failure | Warning |
| E517 | Water Flow Switch Failure | Warning |
| E736 | CH Return Thermistor Failure | Warning |
| E740 | CH Buffer Tank Thermistor | Warning |